sorbet: Handle before blocks using let values from within tests

[issyl0]

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OpenAI GPT-5.3 Codex for finding all occurrences of this pattern that upset Sorbet, with local review and testing.

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• Enable typechecking of tests where a top-level before or subject block references a value that is only defined via let in tests, which Sorbet cannot resolve statically.
• The actual value of the let that matters for the test and its setup is set in the individual tests, which will always override the top-level let value that we set.

[MikeMcQuaid]

Thanks, looks good when 🟢!

[github-code-quality]

Code Coverage Overview

Languages: Ruby

Ruby / code-coverage/simplecov

The overall coverage in the sorbet-doesnt-unders... branch is 75%. The coverage in the main branch is 78%.

Show a code coverage summary of the most impacted files.

File	main 9e7331e	sorbet-doesnt-unders... 8862004	+/-
cask/info.rb	96%	0%	-96%
cask/installer.rb	91%	28%	-63%
cask/artifact/a...ct_uninstall.rb	89%	32%	-57%
cask/audit.rb	63%	25%	-38%
cask/cask_loader.rb	96%	65%	-31%
bundle/extensions/flatpak.rb	37%	94%	+57%
extend/os/linux/diagnostic.rb	0%	67%	+67%
os/linux/elf.rb	0%	86%	+86%
extend/os/linux/sandbox.rb	0%	95%	+95%
extend/os/linux...ystem_config.rb	0%	99%	+99%

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_{Updated May 31, 2026 14:52 UTC
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[Copilot]

Pull request overview

This PR aims to improve Sorbet typechecking for RSpec tests where before/subject blocks reference values that are only defined via let in nested examples (which Sorbet can’t always resolve statically).

Changes:

• Switch a few test files from # typed: false to # typed: true.
• Add top-level placeholder let values (e.g., who_output, string, required_ruby_version, languages) so Sorbet can resolve references from before/subject.
• Add old_tap/new_tap and tap let values in some specs to make referenced methods visible to Sorbet.

Show a summary per file

File	Description
Library/Homebrew/test/utils/user_spec.rb	Enables typechecking (typed: true) and adds a placeholder let(:who_output) referenced by a before stub.
Library/Homebrew/test/utils/string_inreplace_extension_spec.rb	Enables typechecking (typed: true) and adds a placeholder let(:string) used by subject.
Library/Homebrew/test/utils/ruby_check_version_script_spec.rb	Enables typechecking (typed: true) and adds a placeholder let(:required_ruby_version) used by subject.
Library/Homebrew/test/formulary_spec.rb	Adds top-level let(:old_tap)/let(:new_tap) for tap-migration setup used in an outer before.
Library/Homebrew/test/cmd/untap_spec.rb	Adds let(:tap) inside shared examples for installed formula/cask tests.
Library/Homebrew/test/cask/dsl_spec.rb	Adds a placeholder let(:languages) referenced by a before that configures cask.config.languages.

Copilot's findings

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• Files reviewed: 6/6 changed files
• Comments generated: 2